U.S. patent number 8,653,786 [Application Number 12/838,898] was granted by the patent office on 2014-02-18 for cordless mower including battery with two charging connectors.
This patent grant is currently assigned to Black & Decker Inc.. The grantee listed for this patent is Florin Baetica, P. Wade Mooney, Richard P. Rosa. Invention is credited to Florin Baetica, P. Wade Mooney, Richard P. Rosa.
United States Patent |
8,653,786 |
Baetica , et al. |
February 18, 2014 |
Cordless mower including battery with two charging connectors
Abstract
A battery-powered lawn mower includes a deck, a latch assembly,
a battery, a motor and a blade. The deck is supported by wheels and
defines a pocket. The latch assembly is coupled to the deck and is
movable between a locked position and a fully opened position. The
battery is secured within the pocket by the latch assembly in a
first configuration and is removable from the pocket in a second
configuration. The motor is supported by the deck and electrically
coupled to the battery in the first configuration. The blade is
coupled to the deck and driven by the motor. During operation, the
battery powers the motor to drive the blade.
Inventors: |
Baetica; Florin (Brockville,
CA), Rosa; Richard P. (Kingston, CA),
Mooney; P. Wade (Brockville, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Baetica; Florin
Rosa; Richard P.
Mooney; P. Wade |
Brockville
Kingston
Brockville |
N/A
N/A
N/A |
CA
CA
CA |
|
|
Assignee: |
Black & Decker Inc.
(Newark, DE)
|
Family
ID: |
45497395 |
Appl.
No.: |
12/838,898 |
Filed: |
July 19, 2010 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20100275564 A1 |
Nov 4, 2010 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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29361418 |
May 11, 2010 |
D642119 |
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12426499 |
Apr 20, 2009 |
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61048002 |
Apr 25, 2008 |
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Current U.S.
Class: |
320/104; 320/137;
320/115; 56/11.9 |
Current CPC
Class: |
A01D
34/78 (20130101); B60L 53/80 (20190201); A01D
69/02 (20130101); H01M 50/20 (20210101); A01D
34/37 (20130101); A01D 34/58 (20130101); B60L
50/66 (20190201); Y02T 10/7072 (20130101); Y02T
90/12 (20130101); Y02E 60/10 (20130101); Y02T
10/70 (20130101); B60L 2200/40 (20130101); Y02T
90/14 (20130101) |
Current International
Class: |
H01M
6/50 (20060101) |
Field of
Search: |
;320/137,115,107,104
;318/599,139 ;429/96,1,178,187,123 ;56/11.9,10.1 ;180/68.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1584224 |
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Oct 2005 |
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EP |
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1698221 |
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Sep 2006 |
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EP |
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2374346 |
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Oct 2011 |
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EP |
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WO-2008015479 |
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Feb 2008 |
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WO |
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Other References
International Search Report and Written Opinion dated Mar. 8, 2012
for PCT International Application No. PCT/US2011/044336, 8 pages.
cited by applicant .
European Search Report dated Apr. 4, 2012 for European Application
No. 11193653.0, 5 pgs. cited by applicant .
European Search Report dated Jul. 16, 2009 for European Application
No. 09158635.4, 6 pgs. cited by applicant.
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Primary Examiner: Fabian-Kovacs; rpad
Attorney, Agent or Firm: Harness, Dickey & Pierce,
P.L.C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Design
application Ser. No. 29/361,418, filed on May 11, 2010 and a
continuation-in-part of U.S. application Ser. No. 12/426,499, filed
Apr. 20, 2009, which claims the benefit and priority of U.S.
Provisional Application No. 61/048,002, filed Apr. 25, 2008. The
entire disclosure of each of the above applications is incorporated
herein by reference.
Claims
What is claimed is:
1. A battery-powered lawn mower comprising: a mower deck defining a
battery pocket; a plurality of wheels supporting the mower deck; a
motor coupled to the mower deck; a blade received under the mower
deck, the blade being driven by the motor; a battery having a
battery housing, at least one battery cell, a first battery
connector and a second battery connector, the at least one battery
cell being disposed in the battery housing, the first battery
connector being disposed on a first surface of the battery housing,
the second battery connector being disposed on a second, different
surface of the battery housing, the battery being removably
received in the battery pocket such that the first surface of the
battery housing is abutted against the mower deck, the second
battery connector being adapted to be coupled to a charging cable
when the battery is removed from the battery pocket to facilitate
charging of the at least one battery cell; a latch assembly having
a latch lever that is coupled to the mower deck and movable between
a locked position and a fully opened position, the latch lever
securing the battery to the mower deck when the latch lever is in
the locked position, the latch lever clearing the battery pocket
when positioned in the fully opened position to permit the battery
to be removed from and inserted into the battery pocket; and an
electrical system that is electrically coupled to the motor, the
electrical system comprising a mower connector that is coupled to
the mower deck, the first battery connector being configured to
electrically mate with the mower connector when the battery is
received into the battery pocket and the first surface of the
battery housing is abutted against the mower deck; wherein the
latch lever shrouds the second battery connector when the latch
lever is in the locked position.
2. The battery-powered lawn mower of claim 1, wherein the second
battery connector is disposed in a location where it is shrouded by
another element of the battery-powered lawn mower when the battery
is received in the battery pocket and secured to the mower deck
such that the first surface of the battery housing is abutted
against the mower deck so that the second battery connector cannot
be directly mated to the charging cable.
3. The battery-powered lawn mower of claim 1, wherein the latch
assembly comprises an over-center latch.
4. The battery-powered lawn mower of claim 1, wherein the battery
pocket has a first shape and the battery has a second shape that
complements the first shape such that the battery can be inserted
within the pocket in only a single orientation.
5. The battery-powered lawn mower of claim 1, wherein the battery
includes a handle.
6. The battery-powered lawn mower of claim 5, wherein the handle is
defined by the battery housing.
7. The battery-powered lawn mower of claim 1, further comprising a
drive mechanism electrically coupled to the mower connector, the
drive mechanism receiving power from the battery such to cause the
drive mechanism to propel at least one of the wheels.
8. The battery-powered lawn mower of claim 1, wherein the first
battery connector is different from the second battery
connector.
9. The battery-powered lawn mower of claim 1, further comprising a
handle coupled to the mower deck, the handle having a hand
grip.
10. The battery-powered lawn mower of claim 9, wherein a portion of
the mower deck against which the first surface of the battery
housing abuts when the battery is received in the battery pocket is
disposed between a rotational axis of the blade and a rotational
axis about which a rear pair of the wheels rotate, the rear pair of
wheels being two of the wheels that are closest to the hand
grip.
11. The battery-powered lawn mower of claim 10, wherein a center of
the battery is disposed closer to the rotational axis of the rear
pair of the wheels than the rotational axis of the blade.
12. The battery-powered lawn mower of claim 11, wherein a dimension
between the center of the battery and the rotational axis of the
blade is at least twice as large as a dimension between the center
of the battery and the rotational axis of the rear pair of the
wheels.
13. A battery-powered lawn mower comprising: a mower deck defining
a battery pocket; a plurality of wheels supporting the mower deck;
a motor coupled to the mower deck; a blade received under the mower
deck, the blade being driven by the motor; a battery having a
battery housing, at least one battery cell, a first battery
connector and a second battery connector, the at least one battery
cell being disposed in the battery housing, the first battery
connector being disposed on a first surface of the battery housing,
the second battery connector being disposed on a second, different
surface of the battery housing, the second battery connector being
adapted to be coupled to a charging cable when the battery is
removed from the battery pocket to facilitate charging of the at
least one battery cell; a latch assembly having a latch lever that
is coupled to the mower deck and movable between a locked position
and a fully opened position, the latch lever securing the battery
to the mower deck when the latch lever is in the locked position,
the latch lever clearing the battery pocket when positioned in the
fully opened position to permit the battery to be removed from and
inserted into the battery pocket; and a mower connector
electrically coupled to the motor and the first battery connector:
wherein the second battery connector is disposed in a location
where it is shrouded by another element of the battery-powered lawn
mower when the battery is received in the battery pocket and
coupled to the mower deck so that the second battery connector
cannot be accessed to charge the at least one battery cell wherein
the latch lever is the another element of the battery-powered lawn
mower that shrouds the second battery connector when the latch
lever is in the locked position.
14. The battery-powered mower of claim 13, wherein the first
battery connector physically and electrically mates to the mower
connector when the battery is received in the battery pocket and
seated to the mower deck.
15. The battery-powered lawn mower of claim 13, wherein the latch
assembly comprises an over-center latch.
16. The battery-powered lawn mower of claim 13, wherein the battery
pocket has a first shape and the battery has a second shape that
complements the first shape such that the battery is insertable
into the pocket in only a single orientation.
17. The battery-powered lawn mower of claim 13, wherein the battery
includes a handle.
18. The battery-powered lawn mower of claim 17, wherein the handle
is defined by the battery housing.
19. The battery-powered lawn mower of claim 13, further comprising
a drive mechanism electrically coupled to the mower connector, the
drive mechanism receiving power from the battery such to cause the
drive mechanism to propel at least one of the wheels.
20. The battery-powered lawn mower of claim 13, wherein the first
battery connector is different from the second battery
connector.
21. The battery-powered lawn mower of claim 13, further comprising
a handle coupled to the mower deck, the handle having a hand
grip.
22. The battery-powered lawn mower of claim 21, wherein a portion
of the mower deck against which the first surface of the battery
housing abuts when the battery is received in the battery pocket is
disposed between a rotational axis of the blade and a rotational
axis about which a rear pair of the wheels rotate, the rear pair of
wheels being two of the wheels that are closest to the hand
grip.
23. The battery-powered lawn mower of claim 22, wherein a center of
the battery is disposed closer to the rotational axis of the rear
pair of the wheels than the rotational axis of the blade.
24. The battery-powered lawn mower of claim 23, wherein a dimension
between the center of the battery and the rotational axis of the
blade is at least twice as large as a dimension between the center
of the battery and the rotational axis of the rear pair of the
wheels.
Description
FIELD
The present disclosure relates to lawn mowers and more specifically
to a cordless electric lawn mower.
BACKGROUND
Due to concerns regarding urban air pollution, as well as other
factors, electric lawn mowers are gaining in popularity. Moreover,
due to the inconveniences and operating limitations of corded
electric mowers, battery operated cordless electric mowers can be
preferred. As described herein however, such electric and/or
battery operated mowers can have drawbacks.
By way of example, some of these drawbacks can be associated with
the functionality of the battery. Such drawbacks can include
insufficient battery life, and inconvenient battery manipulation
(i.e., such as during installation and removal of the battery from
the mower). Other drawbacks can be associated with self-drive
transmissions. Some electric and/or battery operated mowers can
incorporate a belt-tensioning drive system, whereby the tension on
a set of variable stepped sheaves can be configured to control the
speed of a drive axle from a continuous speed motor. Such a system
however can be inefficient because the self-drive motor must run
constantly at high speed, thereby constantly drawing maximum power.
Furthermore, as is known in the art, efficiency losses can be
observed in such a slipping belt system. According to other
drawbacks associated with battery operated mowers, in some
instances during high-load grass cutting (i.e., wet, and/or thick
grass), the cutting motor(s) can reduce in operating speed.
Typically however, the output speed of a self-drive motor is
unchanged regardless of the high-load grass cutting. In this way,
cutting performance as a whole can degrade because the speed of the
self-drive motor is not adjusted in view of a given cutting
condition.
According to some other drawbacks associated with electric and/or
battery operated mowers, a mulching mode can be incorporated that
is generally inefficient. Additionally, such mowers may require a
switching process between a mulching mode and a discharge mode that
can be cumbersome and present other performance drawbacks. Some
other drawbacks associated with battery operated mowers can include
inadequate driver feedback information. For example, it may be
desirable for an operator to easily obtain information relating to
battery-power, mower blade operation, self-drive motor operation
and/or other information, such as operational faults associated
with the mower.
SUMMARY
A battery-powered lawn mower includes a deck supported by wheels on
a first side and a cutting mechanism having a first motor,
including a first output member. A first cutting blade is driven by
the first output member. A self-drive transmission has a second
motor that selectively communicates an output to a drive axle. A
force feedback controller measures a load on the first motor and
changes an output voltage to the second motor based on the measured
load.
According to other features, the force feedback controller compares
the load to a threshold. The force feedback controller reduces the
output voltage to the second motor based on the load being greater
than the threshold. The load is measured by detecting a current
through a shunt associated with the first motor. A voltage on the
shunt is compared to a threshold voltage through one of an analog
and digital component. The component is operable to change a
resistor divider value in the second motor based on the comparison.
The force feedback controller proportionally varies the output
voltage on the second motor based on the measured load. The force
feedback controller determines an output of amps of current that
are withdrawn by the first motor and pulse width modulates the
second motor by a varying duty cycle based on the
determination.
A battery-powered lawn mower includes a battery and a deck
supported by wheels on a first side. A drive axle is coupled to the
wheels. A self-drive transmission includes a motor and a clutch
assembly. The motor is powered by the battery and has an output
member. The clutch assembly has a driven transfer gear that is
coupled for rotation with the output member, and a clutch cam that
is mounted for rotation with a user input member. An input from the
user input member urges the clutch cam to concurrently rotate about
and translate along an axis, thereby locking the drive axle for
concurrent rotation with the driven transfer gear and the motor
output member.
According to additional features, the battery-powered lawn mower
includes a variable speed circuit assembly that regulates a voltage
delivered to the motor based on a position of the user input
member. The input from the user input member comprises actuation of
a self-drive bail handle. The clutch cam rotates in a first
direction around and translates along a drive axle axis. A biasing
member urges the clutch cam to rotate in a second direction
opposite the first direction upon a release of the self-drive bail
handle. Rotation of the clutch cam in the first direction causes
the clutch cam to translate along the drive axle axis, whereby one
of a tooth or pocket defined on the clutch cam nests with the other
of the tooth or pocket provided on the driven transfer gear,
thereby coupling the driven clutch for concurrent rotation with the
driven transfer gear. The variable speed circuit assembly comprises
a variable speed cam, a potentiometer, a switch and a variable
speed circuit. The variable speed cam defines a recess and a
plurality of cam gear teeth. The cam gear teeth are rotatably
meshed with clutch cam teeth formed on the clutch cam and wherein
rotation of the clutch cam by way of the clutch cam teeth and the
cam gear teeth interaction urges a button extending from the switch
to be actuated. No electricity is passed to the potentiometer until
the switch is moved to a closed state. Rotation of the
potentiometer passes an increasing signal to the variable speed
circuit wherein as the signal increases the voltage out of the
variable speed circuit is increased to the motor.
A battery-powered lawn mower includes a deck supported by wheels on
a first side and a cutting mechanism having a first motor including
a first output member. A first cutting blade is driven by the first
output member. A self-drive transmission has a self-drive
transmission motor that selectively communicates an output to a
drive axle. A battery provides power to the cutting mechanism and
the self-drive transmission. An LCD display is disposed on the deck
and defines an indicator that corresponds to information relating
to the battery, the cutting mechanism and the self-drive
transmission. The LCD display provides information indicative of at
least one of a power level of the battery, a status indicator of
the first motor and a status indicator of the self-drive
transmission motor. The power level of the battery is displayed as
a series of illuminated bars. The indicator is operable to flash or
illuminate in response to a fault detection from one of the cutting
mechanism and the self-drive transmission. The LCD display is
positioned on the deck.
A battery-powered lawn mower includes a battery, a deck supported
by wheels on a first side, a self-drive transmission, a first
handle portion and a second handle portion. One of the first or
second handle portions is configured to move dynamically relative
to the other handle portion. At least one force sensor is disposed
adjacent to the first and second handle portions and is operable to
sense a force based on dynamic movement of one of the first or
second handles and communicate a signal to the self-drive
transmission based on the force. The self-drive transmission is
operable to proportionally vary an output to at least one of the
wheels based on the signal.
According to additional features, the first handle portion is fixed
within the second handle portion. The second handle portion
includes a tubular member. At least one force sensor is selected
from the group consisting of force sensing resistors, piezoelectric
sensors and strain gauges. At least one force sensor comprises a
pair of diametrically opposed force sensors that are arranged on
the first handle portion. A pair of compliant pads are mounted on
an inner diameter of the tubular member adjacent to the respective
pair of diametrically opposed force sensors. The tubular member is
operable to move relative to the first handle portion, whereby the
force sensors communicate a total force to a controller. The
controller communicates a signal to the self-drive transmission to
vary the output to the at least one of the wheels based on the
total force.
A battery-powered lawn mower includes a deck, a latch assembly, a
battery, a motor and a blade. The deck is supported by wheels and
defines a pocket. The latch assembly is coupled to the deck and is
movable between a locked position and a fully opened position. The
battery is secured within the pocket by the latch assembly in a
first configuration and is removable from the pocket in a second
configuration. The motor is supported by the deck and electrically
coupled to the battery in the first configuration. The blade is
coupled to the deck and driven by the motor. During operation, the
battery powers the motor to drive the blade.
A battery-powered lawn mower includes a deck, a mower connector, a
battery, a motor and a blade. The deck defines a pocket in which
the mower connector is arranged. The battery is secured within the
pocket in a first configuration and is removable from the pocket in
a second configuration. The battery includes a first battery
connector for mating with the mower connector and a second battery
connector for mating with a charger cable. The motor is supported
by the deck and is electrically coupled to the battery in the first
configuration. The blade is coupled to the deck and driven by the
motor. During operation, the battery powers the motor to drive the
blade. The first battery connector automatically mates with the
mower connector as the battery is inserted within the pocket.
A removable battery for use with a battery-powered lawn mower
includes a battery housing, at least one cell and first and second
battery connectors. The at least one cell is arranged within the
battery housing. The first battery connector is electrically
coupled with the at least one cell and is configured to mate with a
mower connector of the battery-powered lawn mower. The second
battery connector is electrically coupled with the at least one
cell and is configured to mate with a charger cable.
Further areas of applicability will become apparent from the
description provided herein. It should be understood that the
description and specific examples are intended for purposes of
illustration only and are not intended to limit the scope of the
present disclosure.
DRAWINGS
The drawings described herein are for illustration purposes only
and are not intended to limit the scope of the present disclosure
in any way.
FIG. 1 is a schematic block diagram of the battery-powered mower
according to one example of the present disclosure;
FIG. 2 is a front perspective view of an exemplary battery-powered
mower shown with a battery being installed into a pocket defined on
the mower;
FIG. 3 is a front perspective view of the mower shown in FIG. 2 and
with the battery shown in an installed position;
FIG. 4 is a front perspective view of an exemplary battery shown
with a portion of the battery housing removed to illustrate a
series of cells housed therein;
FIG. 5 is a partial sectional view taken through the pocket of the
mower;
FIG. 6 is a sectional view taken through the pocket of the mower
and shown with an exemplary battery in the installed position;
FIG. 7 is a partial perspective view of a lever and latch
associated with the mower at the pocket;
FIG. 8 is a rear perspective view of the battery illustrating a
first mounting portion according to one example of the present
disclosure;
FIG. 9 is a detailed perspective view of the first mounting portion
shown in FIG. 8;
FIG. 10 is a perspective view of exemplary electrical connectors
according to one example of the present teachings;
FIG. 11 is a perspective view of a mower cable according to one
example of the present teachings;
FIG. 12 is a perspective view of a charger cable according to one
example of the present teachings;
FIG. 13 is a front perspective view of a battery having a foldable
handle according to additional features of the present
disclosure;
FIG. 14 is a perspective view of the battery shown in FIG. 13 with
a portion of the housing removed to illustrate a battery retention
feature shown in a locked position according to one example of the
present teachings;
FIG. 15 is a sectional view taken along line 15-15 of FIG. 14 and
shown with portions of the retention feature engaged to the
structure on the mower in the locked position;
FIG. 16 is a front perspective view of the battery shown in FIG. 13
and shown with the handle in an upright position corresponding to
the retention feature in an unlocked position;
FIG. 17 is a cut away view of the battery of FIG. 16 showing the
retention feature in the unlocked position;
FIG. 18 is a sectional view taken along line 18-18 of FIG. 17
showing the handle in an upright position corresponding to the
retention feature in the unlocked position;
FIG. 19 is a perspective view of an exemplary handle assembly
constructed in accordance to one example of the present
teachings;
FIG. 20 is a cross-sectional view of an alternate handle grip
according to other features of the present disclosure;
FIG. 21 is a perspective view of a self-drive transmission
constructed in accordance to one example of the present
teachings;
FIG. 22 is a perspective detailed view of a variable speed circuit
assembly and clutch assembly of the self-drive transmission
illustrated in FIG. 21;
FIG. 23 is a detailed perspective view of the self-drive
transmission and shown with a drive axle meshed for rotation with
wheel gears disposed on a pair of drive wheels;
FIG. 24 is a perspective view of a first cover of the self-drive
transmission;
FIG. 25 is a detailed perspective view of the variable speed
circuit assembly and clutch assembly shown in FIG. 22;
FIG. 26 is a partial sectional view of the clutch assembly and
shown in an open or unlocked position;
FIG. 27 is a detailed perspective view of the variable speed
circuit assembly;
FIG. 28 is a perspective view of the self-drive transmission shown
with a plate removed from an enclosure associated with the clutch
assembly and variable speed circuit assembly;
FIG. 29 is a partial exploded view of a planetary gear assembly
housing and a carrier transfer gear according to one example of the
present teachings;
FIG. 30 is another exploded view of the planetary gear assembly
housing and carrier transfer gear shown in FIG. 29;
FIG. 31 is a perspective view of the motor and planetary gear
assembly shown with the carrier transfer gear meshed for engagement
with a driven transfer gear clutch;
FIG. 32 is an exploded view of an exemplary planetary gear assembly
and carrier transfer gear according to other features of the
instant disclosure;
FIG. 33 is a flow diagram of a forced feedback speed control
according to one example of the present disclosure;
FIG. 34 is a flow diagram of a forced feedback speed control
according to a second example of the present disclosure;
FIG. 35 is a flow diagram of a forced feedback speed control
according to a third example of the present disclosure;
FIG. 36 is an exemplary circuit diagram associated with the flow
diagram according to the third example in FIG. 35;
FIG. 37 is a plan view of a motor start delay assembly according to
one example of the present teachings;
FIG. 38 is a perspective view of a first and second switch of the
motor start delay assembly of FIG. 37 and shown in an initial
position;
FIG. 39 is a perspective view of the first and second switch shown
in FIG. 38 and shown with a biasing member partially expanded
corresponding to a time delay incorporated between activation of
the first switch and the second switch;
FIG. 40 is a rear perspective view of a battery-powered mower
according to additional features of the present disclosure and
including a user display;
FIG. 41 is a detailed perspective view of the user display shown in
FIG. 40;
FIG. 42 is a plan view of an LCD display according to additional
features;
FIGS. 43 and 44 are detailed views of a self-drive indicator, a
mower blade indicator, and a battery-power indicator of the LCD
display shown in FIG. 42 according to one example;
FIG. 45 is a plan view of an exemplary charger display having a
first battery-power indicator and a second battery-power
indicator;
FIGS. 46 and 47 are detailed views of a battery-power indicator
according to additional features;
FIG. 48 is a plan view of a battery charger display according to
additional features;
FIG. 49 is a bottom plan view of a deck of a mower according to one
example of the present disclosure and having first and second
cutting blades;
FIG. 50 is a front perspective view of the exemplary mower shown in
FIG. 49 and shown with portions of the mower in phantom to
illustrate a first and second motor associated with the first and
second cutting blades;
FIG. 51 is a partial bottom plan view of a mower according to
another example of the present teachings and including a deck
having a first and second volute;
FIG. 52 is an exploded perspective view of the mower deck
illustrated in FIG. 51 and a mulch plug according to one example of
the present disclosure;
FIG. 53 is a partial bottom plan view of a mower according to
additional features;
FIG. 54 is a bottom plan view of the mower of FIG. 53 and shown
with the mulch plug in an installed position;
FIG. 55 is a perspective view of an exemplary battery-powered lawn
mower shown with a battery installed into a pocket defined on the
mower;
FIG. 56 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 55 in a first
configuration;
FIG. 57 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 55;
FIG. 58 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 55 in a second
configuration;
FIG. 59 is a perspective view of the exemplary battery-powered lawn
mower shown in FIG. 55 with the battery being removed from the
pocket;
FIG. 60 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 55 with the battery
removed to illustrate the pocket;
FIG. 61 is a perspective view of the battery of the exemplary
battery-powered lawn mower shown in FIG. 55;
FIG. 62 is another perspective view of the battery of the exemplary
battery-powered lawn mower shown in FIG. 55;
FIG. 63 is another perspective view of the battery of the exemplary
battery-powered lawn mower shown in FIG. 55;
FIG. 64 is a partial perspective view of the battery of the
exemplary battery-powered lawn mower shown in FIG. 55 with a
portion of the battery housing removed to illustrate a series of
cells housed therein;
FIG. 65 is a partial perspective view of a user interface of the
exemplary battery-powered lawn mower shown in FIG. 55;
FIG. 66 is a perspective view of a safety key corresponding to the
exemplary battery-powered lawn mower shown in FIG. 55;
FIG. 67 is a sectional view of the safety key of FIG. 66;
FIG. 68 is a partial perspective view of the battery of the
exemplary battery-powered lawn mower shown in FIG. 55 with an
exemplary charger cable; and
FIG. 69 is a partial perspective view of the exemplary user
interface shown in FIG. 65 with an exemplary charger cable.
DETAILED DESCRIPTION
With initial reference to FIG. 1, an exemplary battery-powered lawn
mower 10 (hereinafter, mower) is schematically illustrated. The
mower 10 can include a battery 12, a cutting mechanism 14 for
driving blade(s) 16, a drive mechanism 18, a force feedback
controller 20, a user interface 22, a main controller 24 and a
display 26. In general, the battery 12 can be adapted to power the
cutting mechanism 14 and the drive mechanism 18. The cutting
mechanism 14 can provide an output for imposing motion onto the
driving blade(s) 16. The drive mechanism 18 can provide an output
for imposing motion onto drive wheels 30.
The main controller 24 can control the application of power from
the battery 12 to the cutting mechanism 14 and/or the drive
mechanism 18 based on an input from the user interface 22. The user
interface 22 can include any suitable device or mechanism such as a
lever on a handle for example. In one example, actuation of a lever
can move a switch between "ON" and "OFF" positions via a cable as
is known in the art. The force feedback controller 20 can be
configured to regulate an output speed of the drive mechanism 18
based on a load detected on the blade(s) 16.
The main controller 24 can be configured to communicate various
electrical outputs to the display 26 representative of various
operational information, such as but not limited to, the power
level of the battery 12, the operational status of the blade(s) 16
and the drive mechanism 18. The display 26 therefore can provide
visual feedback to a user of such operational information.
Battery
With continued reference to FIG. 1 and additional reference to
FIGS. 2-12, the battery 12 will be described in greater detail. The
battery 12 can generally include a battery housing 34 for retaining
cells 36A, 36B and 36C (FIG. 4). In one example, the battery
housing 34 can be formed of rigid plastic. In the particular
example shown, three cells 36A, 36B and 36C are shown connected in
series, however, other configurations are contemplated. The
exemplary battery 12 can provide 36 volts direct current (DC). It
is appreciated that the battery 12 can be configured to provide
other voltages. A handle 40 can be formed at an upper side 41 of
the battery housing 34. A catch 42 defining a groove 44 can be
formed at a forward side 46 of the battery housing 34. A relief 50
(FIG. 4) defining a ledge 52 can be formed at a rearward side 54 of
the battery housing 34. A first mating portion 56 can be formed at
the rearward side 54 of the battery housing 34. A front heel 60 can
be formed at a transition between the forward side 46 of the
battery housing 34 and a bottom side 62 of the battery housing 34.
A rear heel 64 can be formed at a transition between the rearward
side 54 and the bottom side 62 of the battery housing 34.
The battery 12 can be configured to selectively mate with a pocket
66 defined on the mower 10. Prior to describing the mating action
of the battery 12 with the pocket 66, additional features of the
mower 10 will be briefly described. The mower 10 can define a deck
70. The deck 70 can provide a mounting structure for various
components of the mower as will be described and can generally form
a barrier to the blade(s) 16. A pair of lateral walls 72 and 74 can
extend upward from the deck 70. The pair of lateral walls 72 and 74
cooperate with a forward boundary 76 (FIG. 5), a rearward boundary
78, and a base 80 to form the pocket 66. The rearward boundary 78
can include a protrusion 82 that generally extends into the pocket
66. A ramp 84 can be formed at a transition between the forward
boundary 76 and the base 80. The pocket 66 is generally centered
between a first and second motor(s) 86 and 88 (FIG. 3) of the
cutting mechanism 14. A second mating portion 90 can be defined on
the mower 10 in an area generally adjacent to the rearward boundary
78 (FIG. 5).
A latch assembly 92 can be provided generally adjacent to the
forward boundary 76. The latch assembly 92 can include a latch 94
and a lever 96. The latch 94 can define a lip 95. As will be
described, the latch 94 can rotate about a latch pivot 100 and the
lever 96 can rotate about a lever pivot 101 to cooperatively secure
the battery 12 within the pocket 66 in an installed position (FIG.
6).
With specific reference now to FIGS. 2, 5 and 6, installation of
the battery 12 into the pocket 66 will be described. At the outset,
a user, while holding the handle 40 can generally advance the
battery 12 downward into the pocket 66 (FIG. 2). As the battery 12
is progressively advanced downward (toward the base 80 of the
pocket 66), the front heel 60 of the battery housing 34 rides along
the ramp 84, thereby urging the battery 12 rearward (toward the
rearward boundary 78 of the pocket 66). During such rearward
movement, the protrusion 82 formed on the rearward boundary 78 can
nest into the relief 50 defined in the rearward side 54 of the
battery housing 34. Concurrently, the first mating portion 56 of
the battery 12 can mate with the second mating portion 90 of the
mower 10. Next, the latch 94 can be rotated about the latch pivot
100 in a direction clockwise as viewed in FIGS. 5 and 6 until the
lip 95 nests within the groove 44 defined on the battery housing
34. Once the lip 95 is engaged to the groove 44, the lever 96 can
be rotated about the lever pivot 101 in a direction
counter-clockwise as viewed in FIGS. 5 and 6 to positively secure
the latch assembly 92 in a secure position (FIG. 6). As best viewed
in FIG. 3, the latch 94 can provide a wide gripping area along the
catch 42 of the battery housing 34 for ease of use and sufficient
retaining strength. While an over-center latch 94 is shown, other
latching configurations are contemplated such as sliding latches or
rotating latches for example. Furthermore, while the latch assembly
92 has been described near the front of the pocket 66 (e.g. at the
front of the deck 70), the latch assembly 92 may be provided
elsewhere on the deck 70 for communicating with the battery 12.
Likewise, additional latch assemblies can be provided for
cooperative retention of the battery 12.
As can be appreciated, the battery 12 can be secured to the deck 70
with one simple latching operation at a convenient location near
the front of the deck 70. The battery 12 is positioned near the
center of the deck 70 so that the mower 10 is well-balanced and
stable. The battery 12 is made in a narrow shape, with the battery
cells 36A, 36B and 36C standing on end (FIG. 4), so that the
battery 12 can be positioned generally between the first and second
motor(s) 86 and 88 of the cutting mechanism 14. The user can
maneuver the mower 10 easily and the tipping over of the mower 10
is inhibited.
With reference now to FIGS. 8-12 additional features of the first
mating portion 56 of the battery 12 will now be described. The
mower 10 is electrically connected to the battery 12 by way of
coupling the first and second mating portions 56 and 90 together
(FIG. 6). The first mating portion 56 can define a recess 110
having various electrical battery connectors 112 positioned
therein. In the particular example shown, three Anderson-type
electrical connectors 112 are provided. Those skilled in the art
will appreciate that other electrical connectors may be used. The
electrical battery connectors 112 can include a first positive
battery connector 114, a second positive battery connector 116 and
a negative battery connector 118. The first positive battery
connector 114 can be configured for powering the mower 10. The
second positive battery connector 116 can be configured for
charging the battery 12. The negative battery connector 118 can be
configured for powering and charging. Other configurations are
contemplated.
The second mating portion 90 can extend from a mower cable 120
(FIG. 11). The second mating portion 90 can define an extension
portion 122 for being received into the recess 110 of the first
mating portion 56 (FIG. 9). The second mating portion 90 can define
various electrical mower connectors 126 positioned thereon. Again,
Anderson-type electrical connectors 112 are shown by way of
example. The electrical mower connectors 126 can include a negative
mower connector 130 and a positive power mower connector 132. As
can be appreciated, in a mated position (FIG. 6), the negative
battery connector 118 (FIG. 9) is electrically coupled to the
negative mower connector 130 (FIG. 11) and the first positive
battery connector 114 (FIG. 9) is electrically coupled to the
positive power mower connector 132 (FIG. 11).
A charger cable 134 is shown in FIG. 12. The charger cable 134 can
define a third mating portion 136 having an extension portion 138
for being received into the recess 110 of the first mating portion
56 of the battery 12. The third mating portion 136 can define
various electrical charger connectors 140 positioned thereon.
Again, Anderson-type electrical connectors 112 are shown by way of
example. The electrical charger connectors 140 can include a
negative charger connector 142 and a positive charger connector
144. As can be appreciated, in a mated position (not specifically
shown), the negative battery connector 118 (FIG. 9) is electrically
coupled to the negative charger connector 142 and the second
positive battery connector 114 is electrically coupled to the
positive charger connector 144. When the charger cable 134 is
connected to the battery 12, the battery 12 can be charged.
The location of the electrical connectors 112 and the mating shapes
of the first mating portion 56 on the battery 12 helps ensure that
the cables (mower cable 120 and charger cable 134) cannot be
connected in an incorrect location or orientation. The
configuration further ensures reliable charging of the battery 12
and reliable power supply to the mower 10. Using the same opening
on the battery housing 34 for the mower cable 120 and the charger
cable 134 ensures that the mower 10 is unplugged while the battery
12 is being charged. The unique shape and configuration of the
connections also helps to ensure that an inappropriate power supply
or tool cannot be connected to the battery 12, the mower 10, or the
charger (not specifically shown).
With reference to FIG. 55, an exemplary battery-powered lawn mower
10' will be described. The battery-powered lawn mower 10' is
similar to and includes the features of mower 10 (FIG. 1) described
herein, except as noted below. The mower 10' includes a deck 700.
The deck 700 provides a mounting structure for various components
of the mower 10' and can generally form a barrier to the blade(s)
16 coupled to the deck 700. The mower 10' includes a cutting
mechanism 14 (FIG. 1) to drive blade(s) 16 (for example, a motor
704) that is supported by the deck 700. It is contemplated that the
mower 10' may include more than one motor, as described above in
regard to mower 10 and motors 86, 88 (FIG. 3). The deck 700 defines
a pocket 710 that can receive a battery 750 (described below) that
is similar to battery 12 (FIGS. 1 and 8-12). The battery 750 is
electrically coupled to and provides the power to operate motor
704, which drives the blade(s) 16. The battery 750 has a shape that
corresponds to the shape of the pocket 710 such that the battery
750 fits snugly within the pocket 710.
With additional reference to FIG. 60, the pocket 710 includes a
base portion 719 with a plurality of walls 715 arranged
substantially perpendicular to the base portion 719. In one
embodiment, the shape of the battery 750 complements the shape of
the pocket 710 such that the battery 750 can be inserted within the
pocket in a single orientation. For example only, pocket 710 can
define one or more recesses 712A-D (FIG. 60) that correspond to one
or more projections 752A-D (FIGS. 62-63) on the battery 750.
Additionally or alternatively, the pocket 710 can include one or
more projections 714A-C that correspond to one or more recesses
754A-C defined by the battery 750. In this manner, the battery 750
can be inserted within the pocket 710 only when the projection(s)
752A-D, 714A-C and recess(es) 754A-C, 712A-D are properly aligned.
Furthermore, the projection(s) 752A-D, 714A-C and recess(es)
754A-C, 712A-D can assist with guiding the battery 750 to the
proper positioning within the pocket 710. Additionally or
alternatively, the walls 715 of pocket 710 can be tapered to assist
in guiding the battery 750 to the proper positioning within the
pocket 710.
The battery 750 within pocket 710 is positioned such that the mower
10' is well-balanced and stable. The battery 750 (and pocket 710)
is positioned rearward of the longitudinal center 702 of the deck
700 such that a user may more easily maneuver the mower 10'.
Furthermore, in a non-limiting example, mower 10' can include a
drive mechanism (such as drive mechanism 18 described herein) for
propelling one or more of the wheels 30 at the rear of the mower,
and the positioning of the battery 750 rearward of the longitudinal
center 702 of the deck 700 can provide additional weight and
traction to the rear wheels 30. The battery 750 and pocket 710 are
also positioned frontward of the rear wheel axle axis 708 in order
to reduce the overall length of the mower 10'. In addition, the
battery 750 and pocket 710 may be positioned in the approximate
center of the width of the deck 700 to increase stability and
inhibit tipping.
In one embodiment, the motor 704 (and the axis of rotation of the
blade 16) is arranged along the longitudinal center 702 of the deck
700. The center 706 of the battery 750/pocket 710 can be positioned
rearward of the longitudinal center 702 by at least fifty percent
of the distance L1 between the longitudinal center 702 and the rear
wheel axle axis 708. In other words, the distance L1 between the
longitudinal center 702 and the rear wheel axle axis 708 is at
least twice the distance L2 between the center 706 of the battery
750/pocket 710. For example only, the distance L1 can be 380
millimeters and the distance L2 can be 160 millimeters such that
the distance L1 is 2.375 times the distance L2.
In order to further increase stability and inhibit tipping of the
mower 10', the depth of the pocket 710 can be increased. Increasing
the depth of the pocket 710 reduces the overall height of the deck
700 with the battery 750 installed. Further, the battery 750 can
comprise a large portion of the overall weight of the mower 10'.
Thus, increasing the depth of the pocket 710 also lowers the center
of gravity of the mower 10'.
With reference to FIGS. 55-58, a latch assembly 720 that is similar
to latch assembly 92 (FIGS. 2-3 and 5-7) is coupled to the deck
700. While latch assembly 720 is an over-center type latch, other
latching configurations are may be substituted therefor, such as
sliding latches or rotating latches. The latch assembly 720
includes a latch 722 and lever 724. The latch 724 engages a latch
catch 755 formed on the battery 750 to secure the battery 750
within the pocket 710 in a first configuration, as shown in FIG.
56. The lever 724 is rotated, as shown in FIG. 57, to disengage the
latch 724 from the latch catch 755. In a second configuration shown
in FIG. 58, the latch 722 is fully opened and completely disengaged
from the battery 750 such that the battery 750 can be freely
removed from the pocket 710. As more fully described below, the
battery 750 can be removed from the pocket 710 by moving the
battery 750 in the direction of the arrow shown in FIG. 59.
For example only, the latching assembly 720 may further include a
biasing member, e.g., a spring that biases the latching assembly
720 to be in the second configuration. Upon releasing the latch 722
from engagement with the latch catch 755, the biasing member may
automatically move the latch 722 to the fully opened position shown
in FIG. 58. In this manner, the latching assembly 720 may be easily
moved from the first configuration (FIG. 56) to the second
configuration (FIG. 58) by a user utilizing one hand. In order to
secure the battery 750 within the pocket 710, a user manually
engages the latch 722 with the latch catch 755 while rotating the
lever 724. Then, the lever 724 is moved to the lock position while
the latch 722 is engaged with the latch catch 755 (FIG. 56).
With reference to FIGS. 55, 60 and 63, in order to electrically
couple the battery 750 with the other components of the mower 10',
a mower connector 716 is provided within the pocket 710. The mower
connector 716 can include one or more projections 717 extending
into the pocket 710 that are configured to mate with corresponding
recess(es) 757 of a first battery connector 756 in a male-female
connector configuration. Additionally or alternatively, the mower
connector 716 can define one or more recess(es) that are configured
to mate with corresponding projections of the first battery
connector 756. The projection(s) 717 and recess(es) 757 may act as
guide features that assist in positioning the battery 750 within
the pocket 710. The mower connector 716 and/or the first battery
connector 756 can be movably mounted to the pocket 710 and battery
750, respectively, to be self-aligning and ensure a proper
connection between the mower 10' and battery 750. In some
embodiments, the latching assembly 720 is used to fully secure and
couple the mower connector 716 with the first battery connector
756.
With additional reference to FIG. 61, the mower connector 716 can
be arranged within the pocket 710 such that the first battery
connector 756 automatically mates with the mower connector 716 as
the battery 750 is inserted within the pocket 710. For example
only, the mower connector 716 can be arranged upon the base portion
719 of pocket 710 and the first battery connector 756 can be
located on a side 759 of the battery 750 that contacts base portion
719 in the first configuration.
In various embodiments, the battery 750 further includes a second
battery connector 758 (FIGS. 61 and 68), e.g., for connection with
a charger cable 780 (FIG. 68). The second battery connector 758
(FIG. 61) can be present on a portion of the battery 750 that is
inaccessible to a user when the battery 750 is in the first
configuration, i.e., secured within pocket 710, such that the
battery 750 cannot be charged through the second battery connector
758 when the mower 10' is operating. Similar to the first and
second mating portions 56 and 90 (FIGS. 8-12), any or all of the
mower connector 716, first battery connector 756 and second battery
connector 758 can include one or more Anderson-type electrical
connectors 112 to ensure proper electrical connections.
The first battery connector 756 is utilized to provide power to the
mower 10' and also to charge the battery 750, while the second
battery connector 758 is used to charge the battery 750. A charger
cable 780 is connected directly to second battery connector 758 to
charge the battery 750 when the battery 750 is removed from pocket
710. With reference to FIG. 68, the charger cable 780 can be
constructed to engage with the second battery connector 758 in a
single orientation. While the battery 750 is secured within pocket
710, the charger cable 780 is connected to an electrical connector
portion 732 associated with user interface 730, as is described
more fully below. User interface 730 may be similar to user
interface 22 (FIG. 1) described herein. Further, user interface 730
is electrically coupled to the mower connector 716 such that power
may be provided to the battery 750 when coupled with mower
connector 716 as described above. In this manner, battery 750 may
be charged whether or not battery 750 is coupled to mower 10'.
An exemplary user interface 730 is shown in FIGS. 65 and 69. User
interface 730 includes an electrical connector portion 732 that has
three electrical connectors 734A-C. Electrical connectors 734A-C
can be any type of electrical connector, such as Anderson-type
electrical connectors 112 (FIG. 10). Electrical connectors 734A and
734B are utilized to connect with charger cable 780 to charge the
mower 10'. Electrical connectors 734A and 734C are utilized to
connect with a safety key 740 (FIGS. 66-67), further described
below. In order to inhibit improper connections, the electrical
connectors 734A-C can be arranged such that the charger cable 780
can be engaged with electrical connector portion 732 in a single
orientation, i.e., connected with electrical connectors 734A and
734B. Similarly, the electrical connectors 734A-C can be arranged
such that the safety key 740 can be engaged with electrical
connector portion 732 in a single orientation, i.e., connected with
electrical connectors 734A and 734C.
Safety key 740 includes two electrical connectors 742A and 742B.
Electrical connectors 742A and 742B are configured to mate with
electrical connectors 734A and 734C of the user interface 730 in a
single orientation. For example only, electrical connectors 742A
and 742B may be coupled by a jumper 744 to electrically couple
electrical connectors 734A and 734C when the safety key 740 is
mated with electrical connector portion 732. Safety key 740
includes a keyed portion 746 that has a shape that corresponds and
complements the shaped of keyed portion 736 of user interface 730.
The keyed portions 736, 746 and electrical connectors 742A, 742B,
734A and 734C may be constructed and arranged symmetrically such
that the safety key 740 can properly mate with electrical connector
portion 734 in either of two orientations, i.e., 742A with 734A and
742B with 734C or 742A with 734C and 742B with 734A.
An exemplary battery 750 will be described with particular
reference to FIGS. 61-64. Battery 750 includes at least one cell
770A-C arranged within a housing 760. For example only, three cells
770A-C can be connected in series and arranged within a housing
760. The housing 760 includes a first portion 762 mated with a
second portion 764. The first battery connector 756 is arranged on
the second portion 764 and the second battery connector 758 is
arranged on the first portion 762.
The battery 750 further includes a first handle 766A and a second
handle 766. The first and second handles 766A-B may be utilized by
a user to insert or remove the battery 750 from the pocket 710. In
a non-limiting example, the first and second handles 766A-B are
monolithically formed with the first portion 762 of the housing
760. The first handle 766A is arranged on a first side 767 of the
housing 760 and the second handle 766B is arranged on a second side
769 of the housing 760 that is opposite the first side.
With reference to FIGS. 60, 61 and 63, the battery 750 is inserted
within pocket 710 as follows. A user positions the battery 750
within pocket 710. For example only, the user may grasp first and
second handles 766A-B in order to lift and position the battery 750
within pocket 710. The battery 750 is properly positioned and fully
inserted within pocket 710 such that the first battery connector
756 engages and mates with mower connector 716. In one embodiment,
the first battery connector 756 engages and mates with mower
connector 716 automatically as the battery 750 is fully inserted
within pocket 710. As described above, various features of the
battery 750 and/or pocket 710 assist in the proper positioning and
insertion of the battery 750 (projections 752A-D, 714A-C, 717,
recess(es) 754A-C, 712A-D, 757, etc.).
Once the battery 750 is fully inserted within pocket 710 and the
first battery connector 756 is engaged and mated with mower
connector 716, the user engages the latch 722 with the battery 750,
for example, latch catch 755. The user then rotates the lever 724
to lock the latch 722 and fully secure the battery 750 within the
pocket 710.
The battery 750 is removed from being fully secured within pocket
710 as follows. A user rotates lever 724 to unlock the latch 722
from engagement with the battery 750. In some embodiments, the
latch 722 automatically disengages from the battery 750 upon being
unlocked. Alternatively, the user manually disengages the latch 722
from battery 750. A user then grasps the battery (such as, first
and second handles 766A-B) in order to remove the battery 750 from
pocket 710. In various embodiments, the mower connector 716
automatically disengages from first battery connector 756 as the
battery 750 is removed from pocket 710.
Battery--Folding Handle
With continued reference to FIG. 1 and additional reference to
FIGS. 13-17, a battery 150 constructed according to additional
features will be described. The battery 150 can generally include a
battery housing 152 for retaining cells, such as cells 36A, 36B and
36C, shown in FIG. 4. In one example, the battery housing 152 can
be formed of rigid plastic. The battery 150 can define a pair of
ears 154 formed at an upper surface 156. The ears 154 can define
bosses 160 formed therein. A pair of openings 162 can be formed
through opposite sides 164 of the battery housing 152. While the
battery 150 is shown generally cube-shaped, it can define other
shapes such as the shape illustrated with the battery 12 (FIG. 2).
The battery 150 can be configured to house cells for providing a
desired voltage of direct current. In one example, the battery 150
can provide 36 volts DC like the battery described above.
The battery 150 can include a folding handle 166 defined at an
upper end. The folding handle 166 can generally comprise a gripping
bar 170, and a pair of arms 172 formed at opposite ends of the
gripping bar 170. Fingers 173 can be formed at the ends of each arm
172. In one example, the fingers 173 can be generally parallel to
the folding handle 166. The fingers 173 can be received by the
bosses 160 in the ears 154 of the battery housing 152. The arms 172
of the folding handle 166 can define heels 174 (FIG. 17). As will
be described in detail below, the folding handle 166 can be
configured to rotate about a pivot axis 176 (FIG. 13) defined
through the fingers 173 between a folded (locked) position (FIGS.
13-15) and an upright (unlocked) position (FIGS. 16 and 17).
With reference now to FIGS. 17 and 18, additional features of the
battery 150 will be described. The folding handle 166 can be
configured to communicate with a retention feature 180 having a
pair of arms 182 extending generally parallel to the upper surface
156 of the battery housing 152. The arms 182 can define cams 183 on
inner ends and locking teeth 184 on outer ends. Posts 185 can be
formed at the inner ends of the arms 182 for cooperatively
retaining a biasing member 186. The locking teeth 184 can be
generally aligned for protruding through the respective openings
162 defined in the battery housing 152 in the locked position
(FIGS. 13-15) and retracting away from the respective openings 162
in the unlocked position (FIGS. 16 and 17). As shown in FIG. 15, in
the locked position, the locking teeth 184 can securely engage a
cutaway or notch 187 formed in a battery receiving area 188 of the
mower 10.
Movement of the folding handle 166 from a folded (locked) position
to an upright (unlocked) position will now be described. At the
outset, a user can grasp the gripping bar 170 of the folding handle
166 and rotate it from a position shown in FIG. 13 to a position
shown in FIG. 16. As described, the folding handle 166 will rotate
about the pivot axis 176 defined by the fingers 173. During such
rotation, the heels 174 of the folding handle 166 can ride along
the cams 183 defined on the arms 182. As the heels 174 ride along
the cams 183, the arms 182 can be urged toward each other against
the bias of the biasing member 186. Once the arms 182 have moved
toward each other a sufficient amount, the locking teeth 184
retract through the openings 162 and to a position within the
battery housing 152. At this point, the locking teeth 184 are not
engaged with the notch 187 in the battery receiving area 188 of the
mower 10 and the battery 150 can be removed. To return the battery
150 to a locked position, the process is reversed. Notably, the
folding handle 166 is normally biased by the biasing member 186 to
the folded or locked position. The handle configuration provides a
simple, intuitive, one action requirement for a user to remove and
install the battery 150. Other configurations are contemplated. In
one example, a battery cover (not shown) can provide a means for
actuating a locking mechanism.
Turning now to FIG. 19, the user interface 22 will be described
according to one example. The user interface 22 can include a
handle assembly 189. The handle assembly 189 can include handle
frames 190 that generally extend at an angle from the mower deck 70
to a handle grip 191. The handle assembly 189 can include a mower
blade bail handle 192 and a self-drive bail handle 193. The mower
blade bail handle 192 can cooperate with a mower blade start lever
194 and a mower blade control cable 195 to start the blades 16 as
will be described The self-drive bail handle 193 can cooperate with
a self-drive control cable 196 that communicates with the drive
mechanism 18 as will be described. In one example, the mower blade
bail handle 192 can be rotated toward the handle grip 191 about an
axis 197A. The self-drive bail handle 193 can be rotated toward the
handle grip 191 about an axis 197B. According to one example, to
start the blades 16, a user can pull the mower blade bail handle
192 toward the handle grip 191 (rotate the mower blade bail handle
192 about the axis 197A) and hold the mower blade bail handle 192
generally against the handle grip 191, and then push forward (i.e.,
toward the mower deck 70) the mower blade start lever 194. This
action can move the mower blade control cable 195. In one example,
to start the drive mechanism 18, a user can urge the self-drive
bail handle 193 toward the handle grip 191 (rotate the self-drive
bail handle 193 about the axis 197B). As the self-drive bail handle
193 is rotated forward toward the handle grip 191, it moves the
self-drive control cable 196 to actuate the drive mechanism 18 as
will be described in greater detail herein. In one example, as the
self-drive bail handle 193 is rotated forward, it progressively
makes the drive mechanism 18 (and the lawn mower 10 as a whole) go
faster.
Force Sensor Control-Handle
Turning now to FIG. 20, a user interface 22' will be described
according to another example. The user interface 22' can include a
handle grip 191'. The handle grip 191' can include a fixed handle
bar portion 191A and a tubular handle bar portion 191B. According
to one example, the fixed handle bar portion 191A is received
within the tubular handle bar portion 191B. Force sensors 198A,
198B, 198C, and 198D can be arranged on the fixed handle bar
portion 91A. The force sensors 198A-198D can include any force
sensing device, such as force sensor resistors, piezoelectric
sensors, strain gauges or any suitable force sensor. Compliant pads
199A, 199B, 199C, and 199D can be arranged generally adjacent to
the force sensors 198A-198D and be mounted on an inner diameter of
the tubular handle bar portion. During operation, a user can move
the tubular handle bar portion 191B relative to the fixed handle
bar portion 191A. Such movement can be sensed by the force sensors
198A-198D to determine a total pushing force or a total pulling
force. In one example, the sum of the total force can be
communicated to a controller, such as the main controller 24 (FIG.
1). The main controller 24 then can communicate a signal to the
drive mechanism 18 (or more specifically the self-drive motor 210,
as will be described in relation to FIG. 21 herein) corresponding
to a desired output. In one example, the desired output can be a
drive torque or an output speed that is proportional to the summed
force sensed by the collective force sensors 198A-198D.
Self-Drive Transmission
With continued reference to FIG. 1 and additional reference to
FIGS. 21-32, the drive mechanism 18 will be described in greater
detail. The drive mechanism 18 according to the present disclosure
includes a self-drive transmission 200. In general, the self-drive
transmission 200 includes a clutch assembly 202, a variable speed
circuit assembly 204 and a planetary gear assembly 206. The
self-drive transmission 200 translates a rotational output 208 of a
self-drive motor 210 into a rotational output of a drive axle 212.
The drive axle 212 can define pinion gears 214 on opposite ends.
The pinion gears 214 can define pinion teeth 216. The pinion teeth
216 can be rotatably meshed with wheel gear teeth 220 defined
around wheel gears 222. The wheel gears 222 as best shown in FIG.
23 can be disposed around an inboard hub 226 of the respective
drive wheels 30. According to some prior art configurations, a belt
tensioning drive system can be provided, whereby the tension on a
set of variable stepped sheves control the speed of a drive axle
from a continuous speed motor. Such a configuration can be
inefficient for a small separate drive motor because the motor must
run constantly at maximum speed, thereby constantly drawing maximum
power. As will be described herein, the self-drive transmission 200
according to the present teachings, by way of the variable speed
circuit assembly 204 can provide only enough voltage to allow the
self-drive transmission 200 to achieve the desired speed. In this
way, power losses can be minimized.
With specific attention now to FIGS. 21-26, the clutch assembly 202
will be described in greater detail. The clutch assembly 202 can
generally include a carrier transfer gear 230 having carrier teeth
232 that are rotatably meshed with driven teeth 234 formed around a
driven transfer gear/clutch 236. The carrier transfer gear 230 can
be rotatably disposed for concurrent rotation with a carrier
transfer gear shaft 240. According to one example, the carrier
transfer gear shaft 240 can be co-linear to a motor output axle 242
(see FIG. 26). With reference to FIG. 26, the clutch assembly 202
can further comprise a driven clutch 244, a clutch cam 246, a first
biasing member 248, and a second biasing member 250.
According to the example shown in FIG. 26, the driven transfer
gear/clutch 236 can be mounted for rotation about a drive axle axis
238 defined by the drive axle 212. As shown in FIG. 26, the driven
clutch 244 can define a clutch tooth 252 that is selectively
engageable with a notch 254 formed in the driven transfer
gear/clutch 236. The clutch cam 246 can define a stop 256 (FIG. 25)
and a first ramp 260 (FIG. 26). The self-drive control cable 196
(FIGS. 22, 23 and 25) can be fixedly attached to the clutch cam
246. As will be described in detail, translation of the self-drive
control cable 196 (such as by way of actuation of the self-drive
bail handle 193) can cause rotation of the clutch cam 246 about the
drive axle axis 238. More specifically with reference to FIG. 25,
translation of the self-drive control cable 196 in a generally
rightward direction by a user, caused by urging the self-drive bail
handle 193 toward the handle grip 191 (FIG. 19), can cause
counter-clockwise rotation of the clutch cam 246 about the drive
axle axis 238. A release of such a user input force can cause the
biasing members 248 and 250 to urge the clutch cam 246 in a
clockwise direction.
As shown in FIG. 23, the clutch assembly 202 can be generally
contained in a clam shell housing 266 having a first cover 268 and
a second cover 270. As shown in greater detail in FIG. 24, the
first cover 268 can include a planetary gear assembly pocket 272, a
carrier transfer gear pocket 274, a carrier transfer gear boss 276,
a driven transfer gear pocket 280, and a drive axle boss 282. The
first cover 268 can also define a stop surface 284 and a second
ramp 286. As shown in FIG. 22, the stop 256 formed on the clutch
cam 246 can engage the stop surface 284 defined on the first cover
268 to limit over-rotation of the clutch cam 246.
Operation of the clutch assembly 202 according to one example of
the present teachings will now be described. In general, the clutch
assembly 202 can be moved between a disengaged state and an engaged
state. In the disengaged state, the driven clutch 244 is not fixed
for rotation with the driven transfer gear/clutch 236. Therefore,
rotatable motion of the driven transfer gear/clutch 236 is not
communicated through the driven clutch 244 to the drive axle 212.
In the engaged state, the driven transfer gear/clutch 236 is fixed
for concurrent rotation with the driven clutch 244. The driven
clutch 244 can ultimately be fixed for rotation with the drive axle
212. As can be appreciated, rotation on the driven clutch 244 can
cause rotation of the drive axle 212 and rotation of the wheels
30.
The clutch assembly 202 is normally biased toward the disengaged
state by way of the first and second biasing members 248 and 250
(FIG. 26). User actuation of an input device (such as the
self-drive bail handle 193, etc.) can cause rotation of the clutch
cam 246 in the counter-clockwise direction (as viewed in FIG. 25).
During the counter-clockwise rotation of the clutch cam 246, the
first ramp 260 defined on the clutch cam 246 slidably engages the
second ramp 286 (FIG. 24) formed on the first cover 268 to turn a
rotatable motion of the clutch cam 246 into a linear translation of
the clutch cam 246 along the drive axle axis 238. Explaining
further, with reference to FIG. 26, rotation of the clutch cam 246
in the counter-clockwise direction can cause the clutch cam 246 to
translate in a direction leftward. Upon translation of the clutch
cam 246 leftward, the clutch tooth 252 defined on the driven clutch
244 can nest within the notch 254 formed in the driven transfer
gear/clutch 236, thereby coupling the driven clutch 244 for
concurrent rotation with the driven transfer gear/clutch 236. When
tension is released on the self-drive control cable 196, the first
and second biasing members 248 and 250 can return the clutch cam
246 to the disengaged state (FIG. 26).
With reference now to FIGS. 21, 22, 27, and 28, the variable speed
circuit assembly 204 will be described in greater detail. The
variable speed circuit assembly 204 can be generally contained
within an enclosure 292 having a plate 294. In one example, the
enclosure 292 can be integrally formed with the second cover 270 of
the clutch assembly 202. Other configurations are contemplated. The
variable speed circuit assembly 204 can generally define a variable
speed cam 300, a potentiometer 302, a switch 304, and a variable
speed circuit 306 (FIG. 27). The variable speed cam 300 of the
variable speed circuit assembly 204 can generally define a recess
310 formed on an outer hub 312 and a plurality of gear teeth 314
arranged therearound. The cam gear teeth 314 can be rotatably
meshed with clutch cam teeth 318 defined around the clutch cam 246.
Rotation of the clutch cam 246 by way of the clutch cam teeth 318
and cam gear teeth 314 interaction can cause a button 320 extending
from the switch 304 to be actuated. Explained in more detail, a
camming surface formed on the hub 312 at a transition into the
recess 310 can cause a camming action against the button 320 of the
switch 304. When the switch 304 is closed (i.e., depression of the
button 320), a shaft 322 of the potentiometer 302 is rotated.
According to the present disclosure, no electricity is passed to
the potentiometer 302 until the switch 304 is closed, thereby
drawing no electricity from the battery 12. This configuration adds
to the overall run time of the mower 10 by conserving electrical
energy as much as possible. The rotation of the potentiometer 302
passes an increasing signal to the variable speed circuit 306. The
greater the signal strength in, the greater the voltage out of the
variable speed circuit 306 is communicated to the self-drive motor
210. A positive and negative wire 326 and 328 extend from the
variable speed circuit 306 to the battery 12 and/or the main
controller 24 (FIG. 1). In sum, according to one example, as the
clutch cam 246 rotates, it first urges the driven clutch 244 and
the transfer gear/clutch 236 into engagement. The switch 304 is
then activated. The potentiometer 302 is then rotated to increase
the speed of the self-drive motor 210. This allows an operator to
activate the self-drive transmission 200 and vary the travel speed
by urging the self-drive bail handle 193 forward.
With specific reference now to FIGS. 29-31, the planetary gear
assembly 206 according to one example of the present teachings will
be described in greater detail. The planetary gear assembly 206 can
include a planetary gear assembly housing 330 that defines
planetary teeth 332 formed around an inner diameter. A plurality of
planetary gears 334 can be meshed for rotation around the planetary
teeth 332. Each of the planetary gears 334 can define a central
bore 336 that receives a respective pin 340 formed on the carrier
transfer gear 230. The pins 340 can extend from a carrier transfer
gear plate 344 formed on the carrier transfer gear 230. A ring 346
can rest against the carrier transfer gear plate 344. According to
one advantage of the present teachings, the carrier transfer gear
230, carrier transfer gear shaft 240, carrier transfer gear plate
344, and pins 340 can be integrally formed as one unit. According
to one example, these features of the carrier transfer gear 230 can
be die-cast as a single part. The carrier transfer gear plate 344
therefore can act as a journal face that is in contact with the
planetary gear assembly housing 330 in an assembled position. As
can be appreciated, the configuration of the carrier transfer gear
230 can reduce parts count in managing inventory over a carrier
transfer gear that is formed by several separate pieces.
Furthermore, because the carrier transfer gear shaft 240 is
integrally formed with the carrier transfer gear 230, there can be
an elimination of tolerance concerns between an otherwise
separately formed output shaft fitting into a hole provided on a
transfer gear. Furthermore, sound quality can be improved with the
elimination of potential gear-train looseness caused by separate
interfitting components.
FIG. 32 illustrates a planetary gear box 350 according to other
features. The planetary gear box 350 can define a plurality of
planetary gears 352 that are rotatably engaged with teeth 354
formed around an inner diameter of a planetary gear box housing
356. In the example shown in FIG. 32, a carrier transfer gear 360
is shown formed of separately defined components. Specifically, the
carrier transfer gear 360 is part of an assembly that includes
first and second bushings 362 and 364, first and second drive hubs
366 and 368, and a plurality of axles 370 that are correspondingly
received within the central hubs 372 of the planetary gears
352.
Force Feedback Speed Control
According to one implementation of the present teachings, the
cutting mechanism 14 can define one or more cutting motors (such as
cutting motor(s) 86 and 88, FIG. 3) for rotating a corresponding
one or more blades. In some instances, it may be necessary for the
mower 10 to cut heavy and/or long grass. In some examples, as a
result of cutting such heavy and/or long grass, the cutting
motor(s) can be slowed down by the increased effort and drag. As
can be appreciated, if the motor (such as the self-drive motor 210)
associated with the drive mechanism 18 continues operating at the
same speed without accounting for the heavy grass being cut, a
decrease in cut quality may result. In conventional gas-driven
mowers, typically there exists a single motor that provides a
rotational output to the blade and a rotational output to a self
propulsion system. As a result, cutting through heavy grass can
slow down the single motor, thereby slowing down the speed of the
self propulsion system. The mower 10 according to the present
teachings provides a force feedback controller 20 according to
various examples that can sense or measure a load on the cutting
motor(s) and if necessary, slow down the self-drive speed (i.e.,
such as the self-drive motor 210) as a result to optimize the grass
cutting quality of the mower 10.
With reference now to FIG. 33, a flow diagram 400 illustrating
exemplary steps according to a first example is shown. In step 402,
control determines if the cutting motor(s) 86, 88 are on. If the
cutting motor(s) 86, 88 are not on, control ends in step 404. If
the cutting motor(s) 86, 88 are on, control reduces a maximum speed
of the self-drive motor 210 once the cutting motor(s) 86, 88 are
energized in step 406. Control then loops to step 402. In the
method according to the first example, the maximum self-drive speed
is lowered to a predetermined "optimum" maximum cutting speed once
the cutting motor(s) 86, 88 are energized. When a cutting motor
circuit is energized, it can provide a signal to a self-drive
variable speed control to simply lower a maximum range of voltage
to the drive self-drive motor 210. In one example, such a cutting
motor circuit can include a pulse width modulation (PWM)
circuit.
Turning now to FIG. 34, a method according to a second example of
the present teachings is shown at reference 410. In step 412,
control determines if the cutting motor(s) 86, 88 are on. If the
cutting motor(s) 86, 88 are not on, control ends in step 414. If
the cutting motor(s) 86, 88 are on, control measures a load on the
cutting motor(s) 86, 88 in step 416. In step 418, control
determines if the measured load is greater than a threshold. If the
load is not greater than a threshold, control loops to step 412. If
the load is greater than a threshold, control reduces a voltage to
the self-drive motor 210 based on the measured load for a
predetermined time in step 420. Control then loops to step 412. In
one example, a hysteresis algorithm can be provided to delay the
reapplication of the full voltage to prevent the mower 10
oscillating between a slow and a fast condition. In one example,
the load can be measured by detecting a load current through a
shunt associated with the cutting motor(s) 86, 88. The voltage on
this shunt (known resistance) could then be compared to a threshold
voltage through an analog or digital component. This component can
then have the ability to change a resistor divider value in the
motor drive/speed control electronics by a high or a low signal.
For example, if the cutting motor(s) 86, 88 pulled a maximum
measured amplitude value at or above a threshold, then the
self-drive motor 210 would slow down to a predetermined speed. If,
however, the cutting motor(s) 86, 88 pulled less than a given
amplitude, then the drive self-drive motor 210 would speed up to a
specific value.
Turning now to FIG. 35, a method according to a third example of
the present teachings is shown at reference 430 and will be
described. In step 432, control determines if the cutting motor(s)
86, 88 are on. If the cutting motor(s) 86, 88 are not on, control
ends in step 434. If the cutting motor(s) 86, 88 are on, control
measures a load on the cutting motor(s) 86, 88 in step 436. In step
438, control proportionally varies the voltage to the self-drive
motor 210 based on the measured load. Control then loops to step
432. According to one implementation of the third example, for
every amp of current withdrawn by the cutting motor(s) 86, 88, the
force feedback controller 20 would be able to pulse width modulate
the self-drive motor 210 by a varying duty cycle. As a result, the
self-drive motor 210 can be slowed down proportionately with
increased current draw with the cutting motor(s) 86, 88. Likewise,
the speed of the self-drive motor 210 can be increased
proportionately with decreased current withdrawn by the cutting
motor(s) 86, 88. With reference to FIG. 36, an exemplary circuit
440 for the third method is shown.
Mechanically Timed Switching
According to one example of the present teachings, the cutting
mechanism 14 can include two cutting motor(s) (see for example
cutting motor(s) 86 and 88 as illustrated in FIG. 36). As can be
appreciated, it may be desirable to prevent an immediate voltage
draw on the electrical system during initial start up of the
cutting motor(s) 86 and 88. According to one example of the present
teachings, shown in FIGS. 37-39, a motor start delay assembly 442
is provided. In one example, the motor start delay assembly 442 can
be incorporated as part of the cutting mechanism 14 (FIG. 1). In
general, the motor start delay assembly 442 can include a
collection of mechanical springs 444, cables 446, and a first and
second switch 450 and 452, respectively. According to one
implementation, a first cutting motor (i.e., 86) can be started
upon closing of the first switch 450. Similarly, a second cutting
motor (i.e., 88) can be started upon closing of the second switch
452. According to one example, the first switch 450 can be
activated upon initial user request. Once the first switch 450 is
activated, the first motor (i.e., 86) can be started. The spring
444 can be operable to offset the starting time of the second motor
(i.e., 88) by delaying the activation of the second switch 452 by a
predetermined amount of time after the first switch 450 has been
activated. In one example shown in FIGS. 38 and 39, the spring 444
is shown in an extended position (FIG. 39) after activation of the
first switch 450 and prior to activation of the second switch
452.
LCD Display for Battery & Charger Information
Turning now to FIG. 40, according to one example of the present
teachings, the display 26 (FIG. 1) of the mower 10 can include a
liquid crystal display (LCD) display 500 according to one example
of the present teachings is shown. FIGS. 40-44 illustrate various
implementations of the LCD display 500. In general, the LCD display
500 can show information about the mower 10 and battery 12. With
specific reference to FIG. 42, the LCD display 500 can include a
self-drive indicator 502, a mower blade indicator 504, and a
battery-power indicator 506. The LCD display 500 therefore, can
provide information indicative of the battery-power level and
status indicators for the mowing blade motor(s) (i.e., 86 and 88)
and self-drive motor 210.
The LCD display 500 can include a one color LCD or alternatively a
multi-color LCD. In one example, reflective background 510 can be
provided behind an LCD display surface 512. As can be appreciated,
an LCD can have the advantage of being easy to read in sunlight. In
another example not specifically shown, the display can incorporate
a series of LED lights to communicate the same information.
Additionally or alternatively, the mower 10 can use audible beeps
or other sounds to communicate information, such as battery level
or other status or faults. A display screen 514 of the LCD display
500 can include a series of bars 520 or lines to show a power level
of the battery 12. The number of bars 520 to display can be
determined by a measurement of the battery voltage. As is known,
the battery voltage progressively decreases as the motor(s) (i.e.,
86, 88, 210) or other devices on the mower 10 are operating. The
display 26 can compensate for changes in the battery voltage due to
operation of motor(s) (i.e., 86, 88, 210) or other devices, so that
the indication of battery-power level is more accurate. In one
example, the system can use different voltage ranges to determine
the number of bars to display depending on whether any motor(s)
(i.e., 86, 88, 210) or devices are operating.
As described, the display 26 can include the mower blade indicator
504 and the self-drive indicator 502. When a fault, such as an open
circuit is detected at the mower blade motor(s) (i.e., 86 and 88)
or the self-drive motor 210, the appropriate indicator on the
display screen 514 can flash or turn on or off to communicate to
the user that a fault has occurred. A fault such as a circuit
breaker being tripped can be determined by comparing the voltage in
such a circuit on either side of the circuit breaker. The display
screen 514 can include other indicators to show other faults or
changes in status in the mower 10.
As shown in FIG. 40, the LCD display 500 can be positioned near the
rear of the mower deck 70 and/or in toward the user operating
position, so that the user can read the display screen 514, while
operating the mower 10. In one example, the graphics on the display
screen 514 are large enough to be read from several feet away. The
LCD display 500 can be grouped together with such features as a
safety key, instruction labels, battery connection cables to make
user interaction with these features more convenient and efficient,
and to make the manufacturer and assembly of these features more
convenient and efficient.
With reference to FIGS. 45-48 a battery charger LCD display 521
(FIG. 45) and 522 (FIG. 48) are shown according to various
examples. The battery charger LCD display 521 can be configured to
provide various information, such as, but not limited to, a charge
level of a battery 12 being charged, an indicator indicative of a
fully charged battery, an indicator that charging is in progress,
various battery faults, such as an open circuit, damaged battery
pack, overheated battery pack, or over-discharged battery pack. As
shown in these examples, the battery charger can be adapted to
charge two batteries concurrently. As a result, the charger LCD
display 521 or 522 can convey separately information 524, 526
associated with a first battery being charged and information 528,
530 associated with a second battery being charged. As shown in
FIGS. 46 and 47, an exemplary display screen 532 is shown. It is
appreciated that the LCD display 521 can additionally or
alternatively comprise one or a plurality of light emitting diodes
(LED's) for communicating battery charger information.
Twin Blade Mower with Different Sized Blades
With reference to FIGS. 49 and 50, a mower 610 having first and
second blades 612 and 614 according to one example of the present
teachings is shown. The first and second blades 612 and 614 can be
powered by a first and second motor 616 and 618, respectively (FIG.
49). As illustrated, the first blade 612 can be larger than the
second blade 614. As can be appreciated, a cutting diameter of the
first blade therefore can be larger than a cutting diameter of the
second blade.
In one example, the second blade 614 can be positioned generally
downstream of the first blade. The first and second blades 612 and
614 can be positioned for cooperation with a volute 620 of a deck
622. A discharge chute 626 can be defined generally downstream of
the second blade 614. According to some examples of conventional
mulching mowers, each blade of grass can ideally be cut multiple
times. In some examples, cutting a given blade of grass multiple
times can compromise the performance of the grass discharging
feature of a given mower. A grass discharging feature can be
defined as either returning a cut piece of grass downwardly to the
ground or alternatively into a grass bag mounted on the mower. The
twin rotating blade system according to the present teachings,
where the first blade 612 is larger than the second blade 614 can
present an overall more efficient mower. According to one example,
the first blade 612 and the second blade 614 can be arranged at
about 45 degrees relative to each other. The cut swaths of the
first and second blades 612 and 614 can therefore be overlapping to
ensure no grass is left uncut between the two blade cut swaths. In
one example, the first and second blades 612 and 614 can be
counter-rotating. Counter-rotating can allow both blades 612, 614
to discharge out of the rear of the mower 10. In another example,
the first and second blades 612 and 614 can be synchronous rotating
blades. Synchronous rotation can cause the first blade 612 to
discharge into the path of the second blade 614. The second blade
614 can discharge the grass out of the mower 10. The larger blade
612 can be responsible for mulching most of the grass, and the
smaller blade 614, although may mulch some of the grass, can
primarily be used to discharge the grass from the volute 620 to the
discharge chute 626. In various examples, the smaller blade (second
blade) 614 may or may not cut grass, and may be in the same plane
as the larger blade (first blade) 612, or may operate in a
different plane. In the example of both blades 612 and 614 being
arranged on a common plane, they can both be configured to cut
grass and provide an even cut. The blades 612 and 614 can be
configured to mulch and/or discharge the grass at the same time as
cutting it. If the blades 612 and 614 are arranged in different
planes, the first blade 612 can be optimized for cutting and
possibly mulching. The second blade 614 can be optimized for
discharging and possibly mulching. In one example, the first and
second blades 612 and 614 can be operated separately from each
other, so that energy is not being used in a mulching mode. The
smaller blade (second blade) 614 can be configured to turn at a
higher RPM than the larger blade (first blade) 612 for optimal
discharging. In one example, when discharging is not required, a
controller 628 can turn off the second motor 618.
Twin Blade Mower Mulch Plug
With reference now to FIGS. 51-54, a twin blade battery-powered
mower 650 incorporating a mulch plug 652 (FIG. 52) according to the
present teachings will now be described. The twin blade
battery-powered mower 650 can generally define a deck 653 that
defines a first volute 654 and a second volute 656. The first
volute 654 can be configured to define a cutting area of a first
blade (not specifically shown). Similarly, the second volute 656
can define a cutting area of a second blade (not specifically
shown). The first volute 654 can define a first radial wall 668.
The second volute 656 can define a second radial wall 670.
A discharge chute 672 can be formed generally between the first and
second volutes 654 and 656. With specific reference to FIG. 52, the
mulch plug 652 defines a first annular surface 676 and a second
annular surface 678. As shown, the first annular surface 676 can be
configured in a geometry that is complementary to the first volute
654. Likewise, the second annular surface 678 can be configured in
a geometry that is complementary to the second volute 656. With
reference to FIG. 54, the mulch plug 652 is shown in an installed
position inserted through the discharge chute 672. In general, the
mulch plug 652 can reach all the way to the middle of the first and
second volutes 654 and 656 and have a geometry in the area that
meets the first and second volutes 654 and 656 to effectively
create a smooth continuous surface. As a result, the mulch plug 652
can create two distinctive volutes with a crossover area 680
between them on the twin blade battery-powered mower 650 described
herein energy savings is important. The smooth and continuous
volute configuration the mulch plug 652 creates in the installed
position (FIG. 54) can create a continuous surface that discourages
grass build up and increases overall efficiency of the twin blade
battery-powered mower 650.
While the disclosure has been described in the specification and
illustrated in the drawings with reference to various embodiments,
it will be understood by those skilled in the art that various
changes may be made and equivalents may be substituted for elements
thereof without departing from the scope of the disclosure as
defined in the claims. Furthermore, the mixing and matching of
features, elements and/or functions between various embodiments is
expressly contemplated herein so that one of ordinary skill in the
art would appreciate from this disclosure that features, elements
and/or functions of one embodiment may be incorporated into another
embodiment as appropriate, unless described otherwise above.
Moreover, many modifications may be made to adapt a particular
situation or material to the teachings of the disclosure without
departing from the essential scope thereof. Therefore, it is
intended that the disclosure not be limited to the particular
embodiments illustrated by the drawings and described in the
specification as the best mode presently contemplated for carrying
out this disclosure, but that the disclosure will include any
embodiments falling within the foregoing description and the
appended claims.
* * * * *